There is an option to show all menu items to all admin users or other specific privilege users.
By default the option, “show all menu items to all admin” is enabled in the Set Privilege Users tab option. That is why you can still see the menus.
From version 5.0, by default, all admin menu items, admin bar menu items and dashboard widgets will be shown to all administrator users. It is a feature to enable you (as admin) access to restricted menus and widgets. You need to configure Privilege users to customize who can access to all menu items and widgets. Please check the following article to know more about Privilege feature https://kb.acmeedesign.com/kbase/i-want-to-hide-certain-menu-items-for-specific-users-but-not-myself/